Thread recutting fasteners, such as bolts and screws, are known in the prior art and have been proposed in a number of specific forms. These devices have met with varying degrees of success in the marketplace. In some instances, the manufacturing cost of the fastener has proven too high to justify its use commercially. In other cases, where a lower cost self-threading fastener has been realized, its ability to recut threads has been less than desirable.
Accordingly, the simple objective of this invention is to provide a self-threading fastener of the mentioned type which is an improvement over the known prior art in terms of its operational efficiency and which is very simple in its construction and therefore economical to manufacture and practical.
The invention embodies a threaded fastener, such as a bolt or a screw, having a small axial opening in its leading end intersecting and communicating with a right angular transverse opening slightly inwardly of the leading end of the fastener. One end of the transverse opening is intersected by a groove or recess formed in the threads of the fastener and being somewhat deeper than the threads and extending along the shank of the fastener for a distance away from the inner side of the transverse opening. Thread cutting produced by insertion of the self-threading fastener into damaged threads pass from the groove into the transverse opening and then into the axial opening.
Other features and advantages of the invention will become apparent during the course of the following detailed description.